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Version: 7.1.2

SignalR

SignalR is a very popular real-time communication library from Microsoft, especially within .NET framework. It is also available as a JavaScript client. This allows JavaScript applications to connect to data sources originating from various .NET frameworks very easily.

Here's how it looks from JavaScript side:

const connection = new signalR.HubConnectionBuilder()
    .withUrl('/chart')
    .withAutomaticReconnect()
    .configureLogging(signalR.LogLevel.Information)
    .build()

async function start() {
    try {
        await connection.start()
        console.log("SignalR Connected.")
    } catch (err) {
        console.log(err)
        setTimeout(start, 5000)
    }
};
start()

connection.on('add', (newDataPoints) => {
    // newDataPoints: { x: number, y: number }[]
    lineSeries.appendJSON(newDataPoints)
})

And an extract from ASP .NET Core example on the server side:

public struct DataPointXY
{
    public double X { get; set; }
    public double Y { get; set; }
    public DataPointXY(double x, double y)
    {
        X = x;
        Y = y;
    }
}
...
DataPointXY[] dataPointArr = new DataPointXY[] { new DataPointXY(timestamp, measurement) };
await _hub.Clients.All.SendAsync(
    "add",
    dataPointArr,
    cancellationToken: stoppingToken
);

Other topics that are closely related to handling real-time data: